Usually elongated goods such as extruded light metal sections are stacked for further processing in layers in transportation or annealing racks or frames, usually designed as side board pallets.
Optimum use of the transportation frames is made if the goods are stacked at the best possible compactness. Particularly the inner width of the frames should be fully utilized if possible.
Generally cutoff saws are used to divide the lengths as produced into the lengths for processing, and a cut-to-length device serves for adjusting the desired processing lengths at the cutoff saw.
The goods cut to processing lengths then normally are stacked by hand in layers in the transportation frames. This causes a heavy workload for the staff and often leads to production bottlenecks. On the other hand, however, stacking by hand frequently cannot be dispensed with for a variety of reasons.
Automatic stacking devices are known from U.S. Pat. Nos. to Cavenar (4,016,072), Lockhart (1,695,115), Benzing (3,267,782) and Obenshain (3,203,326), and from the German patent originating from Schulte and assigned to J. Banning A. G. (DE No. 8l2 537).
The patent to Cavenar discloses a cut-to-length station for cutting to length elongated goods having transportation means to convey the goods to stacking sections on both sides of the cut-to-length station. The transportation means comprise pick-off arms which may be lifted by air cylinders and thereby pivoted around pivot axes to kick the goods away from the transportation path to both sides thereof.
The patent to Lockhart discloses a rack-and-pinion conveyor mechanism which may be lifted by raising of longitudinally extending angle members which form a carriage movable on longitudinally extending tracks. A complicated device is provided to lift and lower the tracks by actuation of a rod.
The patent to Benzing provides for a stacking section for stacking sheets of paper and comprising a series of stacking sections. The sheets to be stacked are cut from continuous webs or the like and gripped and transported in the stacking section by means of a gripper delivery assembly. Thus, the cut sheets are not supported by rollers from below.
The patent to Obenshain, which as well provides a device for stacking sheets of paper, discloses feeding of the sheets to a stacking section by conveying the sheets over a collecting drum and subsequently over a transferring drum to a stack of sheets.
The patent to Schulte (German Pat. No. 812 537) is concerned with a stacking device for stacking of sheets or strips, e.g. made from metal. Along both side edges of a stacking section endless belts are arranged which are adapted to move a set of rollers along the conveying path in conveying direction. The roller axes are suspended vertically on brackets connected to the endless belts running parallel to and above the side edges of the stacking section. The rollers support the goods to be stacked by their radial back surfaces, which extend substantially in a horizontal plane. The brackets are swingable sidewardly out of the conveying path to allow a transfer of the goods to supports of the stacking section. The supports may be lowered to allow stacking of further goods and may be raised after removal of a stack of goods.
The last-mentioned known device is complicated in its design and does not allow for stacking of a package of slim elongated goods of a considerable width, because the vertically extending rollers are adapted to support solely the elongated goods situated in the areas adjacent the side edges of the stacking device, i.e. not over the whole width of the package.